Air suspension with saddle members

ABSTRACT

A vehicle air suspension system having an air bag located between upper and lower plate-like members further includes a pair of saddle members coupled to the vehicle adjacent each side of the air bag and fixed relative to the upper plate-like member. Each saddle member has a substantially vertically oriented slotlike opening therein through which a pivot shaft extends in the transverse direction of the vehicle. The pivot shaft is fixedly connected to the lower plate-like member and is slidably engaged in the slot-like openings of the saddle for movement in the vertical direction. Rocker arms are rotatably coupled adjacent the ends of the pivot shaft and vehicle wheels are coupled to the ends of the rocker arms. The saddle members substantially restrain the pivot shaft against movement in the longitudinal or lateral direction of the vehicle.

0 United States Patent [151 Gouirand [451 Sept. 19, 1972 4] AIRSUSPENSION WITH SADDLE MEMBERS Primary Examiner-Philip Goodman IAttomey-F. Eugene Davis, III, Robert H. Ware and [72] Inventor. ReneGoulrand, New York, NY. Manem ware & Davis [73] Assignee: JosephMercadante, Greenwich,

Conn. [57] ABSTRACT [22] Filed: March 22, 1971 A vehicle air suspensionsystem having an air bag located between upper and lower plate-likemembers [21] Appl' 126;, further includes a pair of saddle memberscoupled to the vehicle adjacent each side of the air bag and fixed s2U.S. Cl ..2s0/104.s A, 280/124 F, 293/68, relative to the pp Plate-likemember- Each saddle 105 199 member has a substantially verticallyoriented slot-like 51 Int. Cl. ..B60g 5 02 Opening therein through whicha pivot Shaft extend-8' in 5 Field f s h 280/l045 A, 0 5 3 thetransverse direction of the vehicle. The pivot shaft 105/199 R isfixedly connected to the lower plate-likevmember and is slidably engagedin the slot-like openingsof the 56 R f saddle for movement in thevertical direction. Rocker I 1 e erences ed arms are rotatably coupledadjacent the ends of the UNITED STATES PATENTS pivot shaft and vehiclewheels are coupled to the ends of the rocker arms. The saddle memberssubstantially 2,838,321 6/1958 Gou rand ..280/l04.5 R. restrain thepivotshaft against movement the [om 2,624,594 1953 Goulrand ..280/104.5 Rgitudina] or lateral direction of the vehicle 2,906,358 9/1959 Tucker..280/ 104.5 A 2,493,004 1/1950 Mackie ..280/ 104.5 A

27 Claims, 9 Drawing Figures P'ATENTEDSEPI I I v 3.692.325

SHEET 1 (IF 4 PATENTED 19 I973 3.692.325

sum 3 0f 4 FIG. 6

AIR SUSPENSION WITH SADDLE MEMBERS This invention relates to vehicle airsuspension systems, and more particularly to air suspension systemswhich are particularly suitable for use with trucks, buses, railroadcars, and other heavy duty use.

Most known air suspension systems of the type to which the presentinvention pertains incorporate one or more of the following undesirablecharacteristics: they are relatively complicated in construction,require a relatively large number of parts, require the use of a swaybar and generally, require frequent and periodic lubrication of theirvarious moving parts to assure proper operation and to improve the lifeexpectancy of the suspension system. t

The main object of the present invention is to provide improved airsuspension systems which overcome the above disadvantages of the priorart and which utilize a reduced number of parts, which require little orno periodic lubrication and which do not require the use of a sway barand its associated suspension components.

A further object of the present invention is to provide a floatingaction air suspension system which is self aligning and in which metalfatigue is reduced.

SUMMARY OF THE INVENTION:

In accordance with the present invention, the air suspension systemincludes a first plate-like member which supports an air bag from aboveand a plate-like suspension member bearing against the lower surface ofthe air bag. A pivot shaft extending transverse of the FIG. 5 is anenlarged view of the saddle portion as shown in FIG. 2, shows theconstruction in more detail;

FIG. 6 is a view, similar to that of FIG. 2, but of another embodimentof the present invention;

FIG. 7 is a view, similar to that of FIG. 3, but of still anotherembodiment of the present invention;

FIG. 8 generally illustrates 'an embodiment of the present invention foruse in railroad cars, and

FIG. 9 is a fragmentary cross-sectional view of a modification of theembodiment shown in FIGS. 1-5.

DETAILED DESCRIPTION OF THE DRAWINGS:

Referring to FIGS. l-5, there is shown a first embodiment of the presentinvention. A, plate-like member 1 is secured, for example by welding, tochannel-shaped chassis members 2 and 3. The upper surface of an air bag4 bears againstplate 1. Air bag 4 may be connected to plate 1 by meansof bolts (not shown), by bonding, or the like. f

A lower plate-like member 6 is provided which bears upon the lowersurface of the air bag 4. Bolts 7 (FIG. 2'), for example, couple the airbag 4 to lower plate-like member 6. Alternatively, bonding or the likemay be used. The exact location of the bolts 7 may be different than asshown. The closer to the center of the air bag 4 that the bolts arelocated, the softer will be the ride of the vehicle since a largerportion of the air bag 4 will be allowed to flex in the radial directionthereof. Air bag 4 vehicle is fixedly mounted to the suspension memberwhich bears against the lower surface of the air bag. Rocker arms arerotatably coupled at each end of the pivot shaft and vehicle wheels arerotatably mounted to the extension arms of the rocker arms for rotation.Chassis saddle members each with a vertically oriented slot-like openingare fixed relative to the first plate-like member at each side of theair bag. The pivot shaft is slidably engaged in the openings of thechassis saddle members for movement in the vertical direction, thechassis saddle members substantially restraining said pivot shaftagainst movement in the longitudinal or lateral direction of thevehicle.

In accordance with a further aspect of this invention, safetyair-bumpers are provided which are in air-communication with the air inthe suspension system air bag. The air in the air bumpers acts as anadditional air reservoir for the air bags of the suspension system toeffectively softened the resulting ride of the vehicle and to enhancethe performance of the suspension system.

Additionally, the air bumper absorbs vehicle impacts and the air in thesuspension system enhances the impact absorption characteristics of theair bumper.

DRAWINGS:

is preferably coupled to plate 1 in a similar manner.

Secured to the lower plate-like member 6 are reinforcing members 8, 9,l0 and 11, which are shown running in the lengthwise direction of thevehicle. Reinforcing members 8-11 are secured, for example by welding,to plate 6. Reinforcing members 8-11 are also preferably welded totransverse support'members l2 and 13 which are also secured, for exampleby welding, to plate 6.'A'pivot shaft 14 which runs in the transversedirection of the vehicle is secured, preferably by welding, totransverse support members 12 and 13. Saddle members 15 and 16 arefixedly secured respectively to either side'of the chassis members 2 and3 of the vehicle at the upper portions thereof as clearly seen in FIGS.1 and 2. Saddle members 15 and 16 are identical and only saddle member15 will be discussed in detail herein.

The saddle member 15 is generally U-shaped as most clearly seen in FIGS.1, 3 and 4. The curved outline of saddle 15, as seen in FIG. 2, is shownonly by way of example and is not limiting. Any other suitable outline(or shape) which provides the desired structural strength in aparticular application can be used. A reinforcing plate 17 isincorporated in the saddle to increase the strength thereof. The innersurface of the lower U shaped portion of saddle member 15 is lined withrubber 18, or the like, and the pivot shaft 14 is adapted to slide inthe vertical direction in the slot-type journal formed by the rubberlined portion of the saddle 15. The specific manner in which the variouscomponents are secured together is shown in greater detail in FIG. 4 andwill be discussed hereinbelow.

Interpo'sed between the ends of the transverse support members 12 and 13and the saddles 15 and 16 are respective rocker arms 19 and 20. Rockerarms 19 and 20 are identical and only arm 19 will be described. Rockerarm 19 comprises a portion 21 having a rubber- 3 lined 36 journaltherein (see FIG. 5) in which the pivot shaft 14 is rotatably engaged.The rubber lining (bush- II ,ing) 36 in portion 21 acts as a bearing andslightly 23 and 30 of rocker anns 19 and 20.Similarly axle 31 coupleswheels 25 and 27 to remote ends 22 and 29 of rocker arms 19 and 20.

Referringto FIG. 5, theend of the pivot shaft 14 is threaded and aretaining nut 32 is threadably engaged therewith. A'fiber washer 33,orthe like, isinterposed between the surface of the nut-32 and theadjacent outer surface'of the saddle 15. Likewise fiber washers 34 and35 are interposed respectively between the rocker arm 20 and the innersurfacev of saddle 16 and the outer surface of reinforcing member 12.The purpose of washers 33 and 34 is to prevent heat build-up and weardue to friction when the pivot shaft 14 moves up and down relative tothe saddle 16 during vehicle movement and when the rocker arms rotaterelative to the reinforcing members 12 and l3.-At the other end of thepivot shaft, that is, on the side of chassis saddle 15, the constructionis similar to the aforementioned, and is not described in detail. Thewashers 3335 may be made of any suitable material such as brake liningmaterial, etc. a

The upper plate-like member 1 may be additionally resiliently connectedto lower plate-like member 6 by means of flexible cable arrangements 41and 42 which are coupled to plates 1 and 6. The cables 41 and 42 may beas shown and described in'my co-pending applicationSer. No. 110,704,filed Jan. 28, l97l. Each cable set 41 and 42 includes three individualcables. Themanner in which cables 41 and 42 are preferably connected toplates 1 and 6 is shown in said copending application. The cables 41 and42 are shown in FIG. 3 as'spacedfromthe air bag 4; However, as the loadis applied to the vehicle, they preferably bear against bag 4, dependingupon load on the vehicle and on vehicle design. Cables 41 and 42 aid inretaining the plates 1 and 6 in their relative positions and aid inreducing the forces applied to saddle members and 16. Cables 41 and 42may also be arranged with the outer cables diverging from the centralcable to aid in wheel alignment as described in said copendingapplication.

The arrangement of FIGS. 1-5 illustrates the pivot shaft 14 restingagainst the lower surface of the rubber raises, a rocker arm pivots, andthereby causes the pivot shaft 14 to move verticallyupward in therubber-'- when one of the wheels of the vehicle hits a bump, theveffects on the wheels at the other end of the particular rocker armassembly and the effects on the wheels at the other side of the vehicleare reduced to a great degree. This greatly reduces wear on the tiresand it has been foundthat heating up of the vehicle tires is greatlyreduced. By virtue of the sidewalls2a and-3a of the channel chassismembers-2jand'3, respectively, which are preferably spaced from butadjacent to the sides of the air bag 4, sidesway forcesarefurtherredu'ced. There is no need for providing separate-sway bars orthe like. Except for the relative movement between the suspension partswhichhave fiber washers 33, 34 and 35 interposed therebetween, see FIG.5, the suspension system has no moving parts which require lubrication.The life expectancy of the suspension system of the present invention isgreatly improved.v

FIG. 6 shows another embodiment of the present invention using adonutshaped air bag 37 mounted in a manner similar to the air bag 4 of FIGS.l-S. Similar elements are given the same reference numerals and are notfurther discussed in detail. The exact mounting construction of thesaddles, such as shown in FIG. 5, is not shown for the arrangement ofFIG 6. The specific mounting details should be apparent in view of theabove description of FIGS. l-5. I

In FIG. 6 saddle members 38- and 39 have similar rubber linedU-shapedportions as do saddles 15 and 16. The saddles 38 and 39 aresecured somewhat differently to chassis members 2 and 3 and are locatedinboard of rocker arms 19 and 20, whereas saddles '15 and 16 of FIGS.1-5 are located outboard'of rocker arms 19 and 20. This arrangementoperates substan-" tially the same as does the embodiment of FIGS. l-5.

FIG. 7:shows another embodiment of the invention using an air bag 40which is tapered in thelongitudinal direction of the vehicle. Thelocation of the saddles, which may be of the construction shown in FIGS.1-5, that shown in FIG. 6, or the like, is rearward of the center of theair bag 40 and is in the vicinity of the larger portion of air bag 40.Cable arrangements 41 and 42 aid in securing the plate 6 to the upperplate 1 at the front and rear, respectively thereof. The air bag 40 mayadditionally be bolted, bonded, or the like to plates 1 and 6. Thecables 41 and 42 may be as shown and described in my co-pendingapplication Ser. No. 1 10,704, filedJan. 28, 1971. Side cables are notnecessary since thechassis side portions 20 and 3a are provided to bearside loads and the side saddle members prevent sideways movement.

This arrangement is more conservative of space below the chassis. Theadvantages of the tapered air bag 40 are discussed in said co-pendingapplication Ser.

FIG. 8 shows the application of the suspension system of the presentinvention to railroad car suspensions. This arrangement is superior topresent-day suspension arrangements in that a better ride is achieved,the structure is lighter in weight, has substantially no moving partswhich require periodic maintenance, and thereby has a longer usefullife.

Referring to FIG. 8, a typical railroad car includes a member 50 with abearing plate 51 thereon. Bearing plate 51 is preferably made of amaterial such as brakelining material, or the like. If necessary, abearing plate, similar to plate 51, can be provided on the upper surfaceof plate 53. Extending from railroad car member 50 is a downwardlyprojecting pin member 52 which is received in the truck of the railroadcar.

The truck configuration of the present invention includes an upper plate53 which bears on the upper surface of a doughnut-shaped air bag 54. Thelower surface of the air bag 54 rests on a plate-like member 55 whichhas its peripheral edges upwardly curved to conform to' the shape of theair bag 54. The curved peripheral edges of the plate 55 help retain theplate 55 in position with respect to the air bag 54. A curved annularmember 64 extends from the lower surfaceof upper plate 53 to aid inretaining the air bag 54in position relative to plate 53. Ring 64 isoptionally provided.

The air bag 54 may be coupled to the plates 53 and 55 by means, ofbolts, bonding or the like. Bolts, such as bolts 7 of FIG. 2, can beused. Rubber lined saddle members 56 and 57 (saddle member 57 is notshown) are secured to the upper plate 53, for example by welding, and apivot shaft 58, which extends transverse of the vehicle, is slidable inthe vertical direction in saddles 56 and 57. The remaining part of thestructure,

which comprises rocker arms 59 and 60, axles 61 and 62 and the railroadwheels, operatein a similar manner to the suspension system describedwith respect to FIGS. 1-5 herein. The operation of the embodiment ofFIG. 8 should be apparent in view of the foregoing descriptions and adetailed discussion thereof is not included herein.

An opening is provided in the central portion of the upper plate 53 forreceiving the downwardly projecting pin 52 of the railroad car. Aretaining member 63, such as a nut, etc., is secured to the end of pin52 after it is engaged in the upper plate 53 to retain the truck to therailroad car.

Flexible cables, such as cables 41 and 42 of FIGS. l-5, are located atthe front and rear portions of the air bag 54 in a manner similar tothat shown in FIG. 3. Cables, such as cables 41 and 42, may be locatedat the sides of the air bag 54, as well as at the front and rear, tofurther improve rigidity of the overall arrangement.

The above described railroad car suspension is extremely advantageousfrom the point of view of smoothness of ride and also from the point ofview of economy, both in fabrication and maintenance. The air bag 54 iscoupled to an air supply (not shown) as is well known in the art. As theload on the railroad car increases, the air pressure in the air bag 54can be likewise increased to bear same while still providing good shockabsorption and riding characteristics.

FIG. 9 illustrates a modification of the saddle members used in theabove described embodiment. In FIG. 9, elements corresponding to theelements shown in FIGS. l-S are given the same reference designationsfor ease of description.

In the embodiment of FIG. 9, the pivot shaft 14 is spaced on either sidefrom the rubber lining I8 in the saddle member 15. It should be 'clearthat saddle member 16 is of similar construction. The remainder of thevehicle suspension system is not shown in FIG. 9. In the embodiment ofFIG. 9, the provision of the space on either side of the rubber linedside walls of the saddle member 15 aids in reducing wear on the rubberlining 18 and aids in reducing metal fatigue of the components of thesuspension system. In practice, the air bag will at least partiallydissipate the horizontal com ponent of a shock applied to the suspensionsystem when a wheel hits a bump or the like, so that when the pivotshaft 14 impacts the rubber lining l8, the'impact force is reduced. Thisreduces wear on the rubber lining 18 and reduces metal fatigue in thesaddles 15 and 16 and the associated components. In a typicalembodiment, the spacing between the pivot shaft and the side walls ofthe saddle member would be approximately )4: of an inch.

During normal riding of the vehicle, horizontal components of theroad'shocks applied to the vehicle tires are absorbed by means of thecombination of the saddle, the cables and the air bag. However, duringbraking of the vehicle, most ofthe braking torque is absorbed by thesaddle member.

The embodiment of FIG. 9- is particularly suitable for use in railroadcars wherein the vertical shocks applied to thesuspension system arerather small in amplitude. The embodiment of FIG. 9 provides a greaterdegree of self alignment than the previously described embodimentswherein there is substantially no free space between the pivot shaft 14and the rubber lined portion of the saddles.

A further modification of the presentinvention is to eliminate the axleshafts, for example axle shafts 28 and 31 of FIGS. 1-5, and to rotatablysupport each wheel structure only at the ends of its respective rockerarm. By virtue of this arrangement, an independent suspension system isobtained whereby the raising of one wheel due to vehicle impact does notaffect the corresponding wheel on the opposite side of the vehicle asmuch as if a common axleshaft is provided. This type of construction maybe preferable in certain applications.

A further modification to the present invention is to eliminate therubber lining l8 and to provide the pivot shaft with a rubber bushingthereon. This type of construction provides substantially the sameeffects and the use of either one will depend upon the designrequirements in particular applications.

The embodiments of FIGS. 1-9 thus provide a true floating action vehiclesuspension system which is self aligning, which has a reduced number ofmoving parts, and in which metal fatigue is reduced. Further excessivesidesway is prevented without using additional sway bars, or the like.

The flexible cables may be replaced by other equivalent flexibleelements and are shown only by way of example. In certain embodimentsthey may be eliminated, depending upon vehicle requirements and design.

The air suspension of the present invention is provided with an airsupply means (not shown) the design of which is well known. As the loadincreases, the air pressure can be increased either manually orautomatically.

A vehicle using the suspension systems of the present invention may beprovided with an air bumper which is in air communication with the airbags. Such an arrangement is clearly shown, for example, in FIGS. 3 and7. Such an air bumper is more fully described and shown in my co-pendingapplications Ser. Nos. 1 10,704 and 110,703, both filed Jan. 28, 1971.It should be clear that such air bumpers are also usable in airsuspension systems other than those shown herein and in said co-pendingapplications. Such anair bumper enhances the performance of thesuspension system and in turn, the suspension system enhancesperformance of the bumper, enabling the vehicle to safely withstandlarge shocks to the bumper with no substantial damage being incurred.Since shocks to the bumper are more efficiently cushioned, there is lessdanger to the occupants of the vehicle.

The term air is used in this specification and in the claims forconvenience. It should be clear that any other suitable fluidmedium,such as gases or liquids, may be used to practice the concepts of thisinvention disclosed and claimed in the appended claims. a

It should be clear that many other variations and alterations can bemade to the specific embodiments describedabove without departing fromthe present inventive concept as set forth in the accompanying claims.

lclaim:

1. A vehicle suspension system comprising:

a first upper plate-like member coupled to said vehicle;

a second lower plate-like suspension member;

an air bag located between said first and second plate-like members; I

first and second saddle members coupled to said vehicle adjacent eachside of said air bag and fixed relative to said first plate-like member,each saddle member having asubstantially vertically oriented slot-likeopening therein;

a pivot shaft extending transverse of saidvehicle and fixedly coupled tosaid lower plate-like suspension member, said pivot shaft being slidablyengaged in the slot-like openings of said saddle members for movement inthe vertical direction, said saddle members substantially restrainingsaid pivot shaft against movement in the longitudinal or lateraldirection of the vehicle;

first and second rocker arms rotatably coupled adjacent respective endsof said pivot shaft inboard of said saddle members; and

vehicle wheels rotatably coupled to the ends of said rocker arms.

2. A suspension system according to claim 1 wherein the slot-likeopening of each saddle member is a U- shaped opening.

3 A suspension system according to claim 1 wherein each saddle memberincludes a lining of rubber-like material in the respective slot-likeopening. 4. A suspension system according to claim 1 including means forflexibly coupling together said first and second plate-like members atat least one of the front and rear portions of said air bag.

5. A suspension system according to claim 4 wherein said flexiblecoupling means couples together said first and second plate-like membersat both the front and rear portions of said air bag.

6. A suspension system according to claim 5 wherein said flexiblecoupling means includes a flexible cable.

7. A suspension system according to claim 1 wherein said air bag issubstantially round in the horizontal plane of the vehicle.

8. A suspension system according to claim 1 wherein said air bag isdoughnut shaped.

9. A suspension system according to claim 1 wherein said air bag issecured to at least one of said first and second plate-like members.

10. A suspension system according to claim 1 wherein said firstplate-like member is fixedly secured to a vehicle chassis and whereinsaid saddle members are fixedly secured to said vehicle chassis.

11. A suspension system according to claim 1 wherein said first andsecond'saddle members are fixedly secured to said first plate-likemember.

12. A suspension system according to claim 1 comprising a bearing memberlocated between each respective rocker arm and saddle member.

13. A suspension system according to claim 1 wherein said rocker armsare coupled to said pivot shaft via respective rubber bearing members.

14. A suspension system according to claim 1 wherein said air bag has atapered cross-section in the direction of the length of the vehicle.

15. A suspension system according to claim 14 comprising means flexiblycoupling together said first and second plate-like members at at leastthe forward, narrowest cross-section, end of said tapered air bag.

16. A suspension system according to claim 1 wherein aspace is providedbetween said pivotshaft and the side walls of said saddle members toallow relative movement between said'pivot shaft and said saddle membersin the longitudinal direction of said vehicle.

'17. A suspension system according to claim 16 wherein said relativelongitudinal movement is small in relation to the vertical movementbetween said pivot shaft and said saddle members.

18. A suspension system according to claim I wherein said vehicle israilroad car and wherein said first plate-like memberis pivotallyconnected to said vehicle.

19. A suspension system according to claim 18 wherein said firstplate-like member includes an opening and wherein said vehicle includesa downwardly extending pin to be received in said opening to pivotallycouple said first plate-like member to said vehicle.

20. A suspension system according to claim 18 wherein said air bag isdoughnut shaped.

21. A suspension system according to claim 18 wherein said saddlemembers are fixedly coupled to said first plate-like member.

22. A suspension system according to claim 1 wherein said systemincludes an air bumper comprising:

a vehicle cross member located at an end of said vehicle;

a bumper plate; and

a bumper air bag in air-communication with said suspension system airbag and interposed between said vehicle cross member and said bumperplate.

23. A suspension system according to claim 22 wherein said bumper airbag is secured to both said vehicle cross member and to said bumperplate.

24. A vehicle suspension system comprising:

a first upper plate-like member coupled to said vehicle;

a second lower plate-like suspension member;

an air bag located between said first and second plate-like members;

first and second saddle members coupled to said vehicle adjacent eachside of said air bag and fixed relative to said first plate-like member,each saddle member having a substantially vertically oriented slot-likeopening therein;

a pivot shaft extending transverse of said vehicle and fixedly coupledto said lower plate-like suspension member, said pivot shaft beingslidably engaged in the slot-like openings of said saddle members formovement in the vertical direction, said saddle members substantiallyrestraining said pivot shaft against movement in the longitudinal orlateral direction of the vehicle; and

a lining of rubber-like material between said saddle member and saidpivot shaft.

25. A suspension system according to claim 24 wherein said lining ismounted to the inside surface of said slot-like opening in said saddlemembers.

26. A suspension system according to claim 24 wherein said lining ismounted to said pivot shaft in said slot-like opening.

27. A suspension system according to claim 24 wherein a space isprovided between said pivot shaft and the side walls of said saddlemembers to allow relative movement between said pivot shaft and saidsaddle member in the longitudinal direction of said vehicle.

1. A vehicle suspension system comprising: a first upper plate-likemember coupled to said vehicle; a second lower plate-like suspensionmember; an air bag located between said first and second plate-likemembers; first and second saddle members coupled to said vehicleadjacent each side of said air bag and fixed relative to said firstplate-like member, each saddle member having a substantially verticallyoriented slot-like opening therein; a pivot shaft extending transverseof said vehicle and fixedly coupled to said lower plate-like suspensionmember, said pivot shaft being slidably engaged in the slot-likeopenings of said saddle members for movement in the vertical direction,said saddle members substantially restraining said pivot shaft againstmovement in the longitudinal or lateral direction of the vehicle; firstand second rocker arms rotatably coupled adjacent respective ends ofsaid pivot shaft inboard of said saddle memBers; and vehicle wheelsrotatably coupled to the ends of said rocker arms.
 2. A suspensionsystem according to claim 1 wherein the slot-like opening of each saddlemember is a U-shaped opening.
 3. A suspension system according to claim1 wherein each saddle member includes a lining of rubber-like materialin the respective slot-like opening.
 4. A suspension system according toclaim 1 including means for flexibly coupling together said first andsecond plate-like members at at least one of the front and rear portionsof said air bag.
 5. A suspension system according to claim 4 whereinsaid flexible coupling means couples together said first and secondplate-like members at both the front and rear portions of said air bag.6. A suspension system according to claim 5 wherein said flexiblecoupling means includes a flexible cable.
 7. A suspension systemaccording to claim 1 wherein said air bag is substantially round in thehorizontal plane of the vehicle.
 8. A suspension system according toclaim 1 wherein said air bag is doughnut shaped.
 9. A suspension systemaccording to claim 1 wherein said air bag is secured to at least one ofsaid first and second plate-like members.
 10. A suspension systemaccording to claim 1 wherein said first plate-like member is fixedlysecured to a vehicle chassis and wherein said saddle members are fixedlysecured to said vehicle chassis.
 11. A suspension system according toclaim 1 wherein said first and second saddle members are fixedly securedto said first plate-like member.
 12. A suspension system according toclaim 1 comprising a bearing member located between each respectiverocker arm and saddle member.
 13. A suspension system according to claim1 wherein said rocker arms are coupled to said pivot shaft viarespective rubber bearing members.
 14. A suspension system according toclaim 1 wherein said air bag has a tapered cross-section in thedirection of the length of the vehicle.
 15. A suspension systemaccording to claim 14 comprising means flexibly coupling together saidfirst and second plate-like members at at least the forward, narrowestcross-section, end of said tapered air bag.
 16. A suspension systemaccording to claim 1 wherein a space is provided between said pivotshaft and the side walls of said saddle members to allow relativemovement between said pivot shaft and said saddle members in thelongitudinal direction of said vehicle.
 17. A suspension systemaccording to claim 16 wherein said relative longitudinal movement issmall in relation to the vertical movement between said pivot shaft andsaid saddle members.
 18. A suspension system according to claim 1wherein said vehicle is railroad car and wherein said first plate-likemember is pivotally connected to said vehicle.
 19. A suspension systemaccording to claim 18 wherein said first plate-like member includes anopening and wherein said vehicle includes a downwardly extending pin tobe received in said opening to pivotally couple said first plate-likemember to said vehicle.
 20. A suspension system according to claim 18wherein said air bag is doughnut shaped.
 21. A suspension systemaccording to claim 18 wherein said saddle members are fixedly coupled tosaid first plate-like member.
 22. A suspension system according to claim1 wherein said system includes an air bumper comprising: a vehicle crossmember located at an end of said vehicle; a bumper plate; and a bumperair bag in air-communication with said suspension system air bag andinterposed between said vehicle cross member and said bumper plate. 23.A suspension system according to claim 22 wherein said bumper air bag issecured to both said vehicle cross member and to said bumper plate. 24.A vehicle suspension system comprising: a first upper plate-like membercoupled to said vehicle; a second lower plate-like suspension member; anair bag located between said first and second plate-like members; firstaNd second saddle members coupled to said vehicle adjacent each side ofsaid air bag and fixed relative to said first plate-like member, eachsaddle member having a substantially vertically oriented slot-likeopening therein; a pivot shaft extending transverse of said vehicle andfixedly coupled to said lower plate-like suspension member, said pivotshaft being slidably engaged in the slot-like openings of said saddlemembers for movement in the vertical direction, said saddle memberssubstantially restraining said pivot shaft against movement in thelongitudinal or lateral direction of the vehicle; and a lining ofrubber-like material between said saddle member and said pivot shaft.25. A suspension system according to claim 24 wherein said lining ismounted to the inside surface of said slot-like opening in said saddlemembers.
 26. A suspension system according to claim 24 wherein saidlining is mounted to said pivot shaft in said slot-like opening.
 27. Asuspension system according to claim 24 wherein a space is providedbetween said pivot shaft and the side walls of said saddle members toallow relative movement between said pivot shaft and said saddle memberin the longitudinal direction of said vehicle.